Compare the potential benefits of adjuvant toremifene with or without goserelin in premenopausal women with stage I-IIIA, hormonal receptor positive breast cancer accompanied with or without chemotherapy induced amenorrhoea.

This is a single center, randomized, controlled study. Patients undergo surgical resection with standard Doxorubicin/Cyclophosphamide Followed by Docetaxel (AC-T).

Chemotherapy begins within 4 weeks after surgery for patients randomized to arm I-IV. Arm I: patients who didn't have CIA receive oral toremifene daily. Treatment continues for 5 years in the absence of disease progression or unacceptable toxicity. Arm II: patients who had CIA receive toremifene as in arm I. Arm III: patients without CIA receive oral toremifene and goserelin for ovarian function suppression. Arm IV: patients with CIA receive oral toremifene and goserelin for ovarian function suppression. Patients are followed every 6 months for 5 years and annually thereafter.

Inclusion Criteria:

• Written informed consent must be obtained and documented according to the local regulatory requirements prior to beginning specific protocol procedures
• Age of at least 18 and at most 45 years
• Spontaneous and regular menstrual periods before study entry with FSH below 15 mlU/ml in follicular phase
• Histologically confirmed primary breast cancer with the need for anthracycline-based chemotherapy
• Steroid receptor (estrogen and progesterone) positive tumor (diagnosis according to hospital standard-procedures)
• No clinical evidence of local recurrence or distant metastases. Complete staging work-up within 3 months prior to registration. All patients must have (bilateral) mammography or breast MRI, chest X-ray; other tests may be performed as clinically indicated
• Karnofsky-Index >80%
• Life expectancy of at least 10 years, disregarding the diagnosis of cancer
• Adequate organ function including normal red and white blood count, platelets, serum creatinine, bilirubin, and transaminases within normal range of the institution
• Patients underwent standard Doxorubicin/Cyclophosphamide Followed by Docetaxel (AC-T)
• Patients must be available for and compliant to treatment and follow-up. Patients registered on this trial must be treated and followed up at the participating center.

Exclusion Criteria:

• Known hypersensitivity reaction to the investigational compounds or incorporated substances
• Prior cytotoxic treatment for any reason
• Suspected (primary or secondary) ovarian insufficiency
• Pregnant or lactating patients. Patients of childbearing potential must have a negative pregnancy test (urine or serum) within 14 days prior to registration and must implement adequate non-hormonal contraceptive measures during study treatment; prior use of hormonal contraceptives has to be discontinued before first Goserelin injection
• Other serious illness or medical condition that may interfere with the understanding and giving of informed consent and the conduct of the study
• Prior or concomitant secondary malignancy (except non-melanomatous skin cancer or carcinoma in situ of the uterine cervix)
• Concurrent treatment with other experimental drugs or any other anti-cancer therapy
• Concurrent treatment with sex hormones. Prior treatment must be stopped before study entry